Disc harrows ordinarily comprise at least one disc section including a plurality of spaced-apart disc blades mounted on a section shaft which is rotatably supported by the disc harrow. Spacer spools are ordinarily positioned between adjacent disc blades. The section shaft is generally rotatably mounted in spaced-apart bearings which are mounted in bearing brackets secured to the disc section frame means.
In years past, the section shaft had a square configuration with each of the disc blades having a square opening formed in the center thereof which received the square shaft extending therethrough. Many of the previous bearing spools also included a square opening formed therein which received the shaft. In those disc harrows employing square shafts, it was not a problem to prevent relative rotation between the disc blades, bearing spools and shaft. Likewise, in those disc harrows employing square shafts, it was not a problem to prevent relative rotation between the two bearing spool members which comprised the bearing spool. However, the problems connected with the fabrication of square shafts have led many disc harrow manufacturers to utilize round shafts rather than square shafts. It has been found that it is much easier to produce round shafts than to produce square shafts.
The use of round shafts in disc sections creates a serious problem in that relative rotation is experienced between the disc blades and the bearing spools as the disc harrow is moved through the field. Attempts are made to prevent such relative movement by tightening the nut at the end of the shaft but is practically impossible to apply sufficient torque to the nut to prevent such rotation. Relative rotation between the bearing spools and the disc blades creates wear on the ends of the bearing spools which results in the need for constant tightening of the shaft nut. It is only a question of time before the bearing spools must be replaced due to the wear on the ends thereof.
Relative rotation between the bearing spool members which comprise the bearing spool creates wear on the abutting ends of the bearing spool members which also results in the need for constant tightening of the shaft nut.
Therefore, it is a principle object of invention to provide an improved bearing spool.
A still further object of the invention is to provide a bearing spool in combination with a disc blade wherein relative rotation is prevented between the bearing spool and the adjacent disc blades.
A still further object of the invention is to provide a disc section for a disc harrow which permits the use of a round section shaft without the accompanying problems normally associated with such a round section shaft.
A still further object of the invention is to provide a disc section which includes means for preventing relative rotation between the disc blades and the bearing spools as the disc harrow is moved through the field.
A still further object of the invention is to provide a bearing spool comprised of a pair of spool members and means for preventing relative rotation between the spool members.
A still further object of the invention is to provide a bearing spool which is economical to manufacture, durable in use and refined in appearance.